@article{CRMATH_2011__349_7-8_407_0,
     author = {Kirchheim, Bernd and Kristensen, Jan},
     title = {Automatic convexity of rank-1 convex functions},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {407--409},
     publisher = {Elsevier},
     volume = {349},
     number = {7-8},
     year = {2011},
     doi = {10.1016/j.crma.2011.03.013},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/j.crma.2011.03.013/}
}